Paper contribution

Application of ARMR for rock slope design

Harry Saroglou; Neil Bar

Proceedings
EUROCK 2026
Pages
687-692
Submitted
22 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

The engineering behaviour of rock masses is in many cases anisotropic due to the presence of either bedding, schistosity or joints and fractures. Anisotropic rock mass rating (ARMR) has been developed to assist in rockmass classification and design of structures in anisotropic rockmasses. A modified Hoek & Brown failure criterion, that incorporates ARMR rating, has been developed to calculate the strength of transversely anisotropic rock masses in various orientations with the context of rock engineering design. The paper presents the methodology of applying ARMR and the modified Hoek & Brown criterion to design a slope in an open pit in the Dominican Republic. Slope stability analysisis performed using anisotropic rock mass strength in 2D and 3D. It is demonstrated that the modified Hoek & Brown approach for anisotropic rock mass is slightly higher factor of safety compared to the Generalised Hoek & Brown criterion for isotropic rock masses.

Contributors

Authors

  1. Harry Saroglou NTUA & Geocon, Athens, Greece ORCID 0000-0002-5253-7972
  2. Neil Bar Gecko Geotechnics, Kingstown, Saint Vincent and the Grenadines ORCID 0000-0001-7948-2468

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Works cited

References

  1. Bar N, Weekes G (2017) Directional shear strength models in 2D and 3D limit equilibrium analyses to assess the stability of anisotropic rock slopes in the Pilbara Region of Western Australia. Australian Geomechanics Journal, 52(4), pp. 91–104.
  2. Bar N (2024) Digital Twin Concept for the Safe and Economic Design and Management of Rock Slopes. Proc. 6th Regional Symp. on Landslides in the Adriatic-Balkan Region, ReSyLAB2024. Vol. 6, 11, p. 89–97.
  3. Barton N, Bandis S (1980) Some effects of scale on the shear strength of joints. International Journal of Rock Mechanics and Mining Science & Geomechanics Abstracts, 17(1), pp. 69–73.
  4. Bieniawski ZT (1989). Engineering Rock Mass Classification; Wiley: New York, NY, USA.
  5. Cancino C, Lorig L, Bu J, Bar N (2024). Back-analysis for more reliable mine plans at Pueblo Viejo Gold Mine. Proc. Slope Stability 2024.
  6. Hoek E, Carranza-Torres C, Corkum B (2002) The Hoek-Brown failure criterion – 2002 edition. In: Proc. of the 5th Northern American Rock Mechanics Symposium and 17th Tunneling Association of Canada Conference (NARMS-TAC), Toronto, Canada, pp. 267–271.
  7. Itasca Consulting Group, Inc. (2019). FLAC3D – Fast Lagrangian Analysis of Continua in Three Dimensions (Version 7.0). Minneapolis: Itasca.
  8. Martin CD, Kaiser PK, McCreath DR (1999). Hoek–Brown parameters for predicting the depth of brittle failure around tunnels. Can. Geotech. J. 36: 136–151.
  9. Saroglou H, Tsiambaos G (2008). A modified Hoek–Brown failure criterion for anisotropic intact rock. Int. Journal of Rock Mechanics & Mining Sciences, 45: 223–234.
  10. Saroglou C, Qi S, Guo S, Wu F (2019). ARMR, a new classification system for the rating of anisotropic rock masses. Bull. Eng. Geol. Env. 78: 3611-3626. https://doi.org/10.1007/s10064-018-1369-4
  11. Saroglou C, Bar N (2020). The ARMR classification system and the modified Hoek-Brown failure criterion compared to directional shear strength models for anisotropic rock masses. Periodica Polytechnica Civil Engineering, 64(1), pp. 14–19.
  12. Saroglou C (2025). The challenge of Rock Mass Classification of anisotropic rockmasses. Rock Mechanics and Rock Engineering. https://doi.org/10.1007/s00603-025-04681-8.